Circuit-closer.



G. H. SLOANE.

CIRCUIT GLOSER.

APPLICATION IILEDNOV. 23, 190B.

' 1,032,030. Patented July 9, 1912.

UNITED %TATE% FATE @lElFIQE.

GEORGE H. SLOANE, 0F BOSTON, MASSACHUSETTS, ASSIGNOB. OF ONE-HALF TO HER- BERT B. WATERS, OF BOSTON, MASSACHUSETTS, AND HAROLD PLIIVIPTON, OF NEVI- TON CENTER, 1VIA$SACHUSETTS.

CIRCUIT-CLOSER.

To all whom it may concern:

Be it known that I, GEORGE H. SLOANE, citizen of the United States, and resident of Boston, county of Suffolk, Massachusetts, have invented certain new and useful Improvements in Circuit-Closers, of which the following is a specification.

This invention relates to circuit-closers of the type intended to be operated automatically by engagement with some part of the passing car, such as the trolley, and comprises matter divided out from my earlier application for improvements in automatic signaling systems, filed'May 26, 1908, Serial No. 435,157, in which application it was originally disclosed.

In its general features the invention comprises a supporting frame provided with two arc-like strips or terminals, insulated from each other and arranged to lie in contact with a relatively movable arm, one of said terminals being divided into separated sections so that in the middle or neutral position the switch arm lies between said sections out of contact with either of them, means being provided for normally holding said switch arm in said middle position.

A further feature of the invention consists in the construction and relative arrangement of the controlling devices for the switch arm, by which its movement along the terminals is permitted, while it is automatically returned to and kept in the neutral position after the car has passed by.

In the accompanying drawings I have illustrated the preferred mode of practising my said invention.

The figure shown in the drawings is a plan view partly in section, showing the switch arm in the neutral or inoperative. position.

In the practice of my invention, I provide a fixed frame at having extended arms a for carrying the adjacent portion of the trolley wire 00. In the middle part of this arm is pivotally mounted a simple lever b, one end of which is extended adjacent to the trolley wire and carries an anti-friction wheel I). The opposite end of said switch arm or lever Z) is provided with an aperture as shown at Z2 through which are passed the shanks of oppositely disposed plunger rods 0 each of which is provided with an Specification of Letters Patent.

Patented July9, i912.

Divided and this application filed November enlarged head 0 to prevent it from being withdrawn from the aperture which it engages. These plunger rods pass into air chambers or cylinders (Z which are pivotally mounted upon the frame a which serve, as will be hereinafter explained, to entrap the air to afford a yielding resistance to the outward movement of the plunger 0 in opposition to the expansive movement of the retracting springs 0 Beneath the outer end of the switch arm 5 is arranged an arc-shaped terminal or contact plate Z which forms one terminal of the circuit to be controlled by the device. Adjacent and parallel to said contact piece Z is the other contact or terminal which in this case is made in non-continuous sections f f whose inner ends are separated by a considerable space at the point where the switch arm lies when in the neutral or nor mal position. a

As will be seen the switch arm forms a permanent contact with the terminal Z over and in contact with whose surface it is free to travel in either direction. However, the outer end of the switch arm will not come into contact with either section of the divided outer terminal strip until it has been moved some distance from the neutral position. Obviously if the trolley 1 or other projecting portion of the passing car is moving to the right, the outer end of the switch arm 5 will travel along the contact terminal Z until it forms a contact with the left hand sect-ion f, thereby closing the circuit. After the trolley has passed out of engagement with the inner end of the trolley arm, the spring retracted plunger 0 to the right of the switch arm serves to return it to the neutral position. By reason of the loose or sliding engagement between the plunger rods and the lever Z), the movement of the lever toward the plunger does not affect the position of the plunger, while the movement of the arm away from the plunger serves to draw in the plunger and compress its actuating spring so that when the arm is released from contact with the car the spring acts to restore the plunger to normal position. In order to insure suflicient durationof contact, means are provided for retarding the return of the plunger to normal position under the influence of its actuating spring. To effect this the plunger is fitted closely into an air cylinder whose outer end is provided with air inlets 0 covered by an ordinary flat valve 0 arranged to admit air during the inward or spring-compressing movement of the plunger. This valve 0 serves to trap or confine the air on the return or outward traverse of the plunger. As it is desired, in order to prevent sparking and the burning of contacts, to cause the plunger to make a quick sudden movement at the point where the contact between the switch arm and the terminal f is broken, I provide a by-pass 0 for conducting the compressed air from one side of the plunger to the other after the plunger has passed by the inner port 0 on its outward traverse. During the first part of the outward traverse the only vent for the confined air in the air chamber is the small orifice 0* but after the plunger has moved out-ward far enough to uncover the port 0 as illustrated in the drawings, the relatively large by-pass 0 allows the air pressure to become equalized on both sides of the plunger, thus stopping all retardation of the plunger movement caused by the air pressure. Consequently as soon as the port 0 is uncovered in the manner described, the plunger and also the switch arm makes a quick jump or movement. This being timed by the position of the parts to take place just as the switch arm is on the point of moving off from the inner end of the contact piece f.

By the above described construction and arrangement it will be seen that the switchcontrolling devices oppose each other only when the switch arm is in the middle or neutral position, the compression springs at this point being balanced against each other. As soon as the lever is moved by positive means in either direction, it begins to compress one spring while relieving the tension on the other spring without affecting the position of its plunger. Moreover, it will be observed that the return movement of the plunger or piston 0 under the influence of the compressed spring 0 is limited by the outer end of the dash-pot so that no exact balance of the opposing springs is required to be maintained. Furthermore, owing to the sliding connection between the plunger rods 0 and the contact arm or lever b, the compression of one spring has no effect upon the other, each being independent so that no bad consequences result if one spring should become materially weaker than the other. Indeed, if one spring were broken the other spring, owing to the stop limit, would be prevented from moving the contact lever from the neutral or open position to form a contact.

That I claim is:

1. An automatic circuit-closer embracing in its construction, a supporting frame, parallel contact terminal strips carried thereby, one of said terminals being divided into two separate parts each insulated from the other, a switch arm mounted to travel along both of said terminals in contact therewith, and means for automatically returning said switch arm to the neutral or open position to break the circuit, and stops for limiting the movement of said returning means to prevent them from moving the switch arm beyond the neutral or open position, substan tially as described.

2. An automatic circuit-closer embracing in its construction, a supporting frame, parallel contact strips mounted thereon to form the terminals of an electric circuit, one of said terminals being interrupted at its middle portion, a switch arm having permanent sliding contact with one terminal and inter mittent contact with the divided terminal, a pair of spring-actuated members arranged on opposite sides of said switch arm acting respectively to return said switch arm to the neutral or open position in whichever direction the switch arm is moved, and stops for limiting the movement of said members in order to prevent either one of them from moving the switch arm beyond the neutral position on its return, substantially as described.

'3. An automatic circuit-closer embracing in its construction a supporting frame, parallel contact terminal strips carried thereby, one of said terminals being divided into two separate parts each insulated from the other, a switch arm mounted to travel along both of said terminals in contact therewith, a pair of spring-actuated members for returning the switch arm to neutral or open position after said switch arm has been moved in either direction, each of said actuating members having a separate sliding connection with the arm whereby each acts inde pendently of the action of the other member, substantially as described.

4. A circuit-closer embracing in its construction a supporting frame, two contact strips forming the opposed terminals of an electric circuit, one of said terminals comprising separated sections, a switch arm adapted to be engaged and moved from side to side by a passing car, and oppositely arranged spring-pressed plungers having engagement with said switch arm and means for limiting the operative movement of said plungers whereby said plungers act to normally retain the arm in neutral position between the separated sections of said terminal, substantially as described.

5. A circuit-closer embracing in its construction a supporting frame, contact strips arranged thereon to form terminals of an electric circuit, a swinging arm arranged when moved from neutral position to form an electrical connection between said terminals, oppositely arranged spring-pressed plungers having sliding engagement wit-h said switch arm to retain it normally in neutral position, substantially as described.

6. The combination of the contact plates, the switch arm movable to and fro over said contact plates to form an electrical connection between them, oppositely arranged spring-pressed plungers, plunger rods extending loosely in opposite directions through a receiving aperture formed in said switch arm and being provided with means for preventing their withdrawal through said aperture, substantially as described.

7 An automatic circuit closer embracing in its construction a supporting frame, a swinging arm thereon adapted to be engaged and moved by a passing car, parallel contact strips carried by said frame one of which is divided midway of its ends to form separate parts insulated from each other and included in different electric circuits, a pair of oppositely disposed dash pots pivotally mounted on said-frame spring pressed pistons mounted therein and having a pulling engagement with said lever by which they move with said lever in one direction and slide through it in the opposite direction the springs being arranged to hold the lever normally in the middleposition to maintain an open circuit, the lever acting according to the direction of movement of the passing car to close one or the other of said circuits by contact with the difi'ercnt portions of the divided contact piece, substantially as described.

In witness whereof, I have subscribed the above specification.

GEORGE II. SLOANE. In the presence of GEO. N. GODDARD, KATHARINE A. DUGAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. C. 

